There is a myriad of common eye disease known in the field of Ophthalmology that benefit from the use of warm compresses applied to the periocular skin. A combination of heat application and scrubbing the eyelids with a mild detergent (e.g., a pH-controlled “baby” shampoo) is the currently accepted means of achieving proper eyelid hygiene, and is the common denominator in the treatment of a variety of very common eye conditions.
Acutely inflamed internal or external hordeola or chalazia (Collectively referred to as Sties) are probably the most widely recognized and accepted indications for using warm compresses on the eyes. These conditions are extremely common, they're recurrent, and occur in children and adults alike, with equal distribution in males and females. Sties are small “lumps” that can form over or under the eyelids, or on the bases of the eyelashes. They typically result from the clogging of oil (sebacious) or sweat glands around the eyelashes or inside the eyelid, and are thought to be brought about by bacterial overgrowth. They can cause tremendous redness, tenderness, pain, tearing and even light-sensitivity, followed by progressive swelling in a small area or the entire eyelid.
Patients often use a warm tea-bag or a towelette that they hold under warm running water, both of which lose heat within mere seconds. Some run their eyes under hot tap water or try microwave-heated compresses with resulting second-degree burns severe enough to have even been reported in the scientific literature. Some specialists advocate the use of a boiled egg or a warm potato wrapped in a thin towel (burrito) to provide heat for a longer duration of time. These methods of applying heat are often either not hot enough or not lengthy enough to be effective, and on the same token, can be hot enough to be harmful to the delicate periocular skin.
The application of heat and pH-controlled detergent (e.g., “baby shampoo”) scrubs has also been advocated toward the treatment of many other ocular conditions such as blepharitis (staphylococcal vs. seborrheic), meibomian gland dysfunction, preseptal/orbital cellulitis, and dry eye syndrome.
In the case of blepharitis, the addition of a mild, broad-spectrum antibiotic (e.g., erythromycin or bacitracin), even steroids (e.g., prednisolone acetate 1% ophthalmic solution) may be supplemented with the warm pH-controlled shampoo scrubs per the discretion of the ophthalmologist.
Blepharitis refers to chronic inflammation of the eyelids, and is one of the most common disorder of the eye. Blepharitis may be anterior, e.g. staphycoccal, seborrheic or posterior, e.g. meibomian gland dysfunction.
Blepharitis is often the underlying reason for eye discomfort, redness and tearing, burning, itching, light sensitivity, and an irritating, sandy, gritty sensation that is worse upon awakening.
Warm compresses followed by lid scrubs is an element of effective blepharitis control. Many ophthalmologists recommend cotton-tip applicators be used to scrub the eyelids and lashes with a pH-controlled shampoo, before or after the application of moist heat. Not only is this exercise tedious and inconvenient for even young, healthy individuals, but is quite a difficult task for children or for the elderly, especially those who suffer from arthritis, those who fatigue easily, have poor near visual acuity, or those whose hands shake. The inconvenience of this ritual is a common cause of poor compliance and treatment failure frequently encountered in clinical practice.
The recommended step-by-step treatment for sties and blepharitis is to:                1) cleanse the oily eyelid margin with a non-toxic (preferably antibacterial) detergent,        2) massage the eyelids to help “unclog” the pores, and        3) provide enough heat to:                    i) help open the clogged pores,            ii) emulsify the lipogranulomatous component of the meibomian contents (like melting butter to turn it into fluid), which would aid drainage and absorption, and            iii) improve blood flow to the affected site to expedite absorption.                        
Acute hordeola, if not treated properly initially, can turn into chalazia, which are hard, painless eyelid masses, and require intralesional steroid injections, even surgical debridement, both of which could be easily prevented by proper and timely intervention.
On a different note, the bacterial flora residing on the eyelid margins has been known to be a source for devastating eye infections (endophthalmitis) following any type of ocular surgery, including LASIK, Corneal Transplantation, Cataract, Glaucoma, and Retinal surgery). In fact, in the face of poor eyelid hygiene or active blepharitis, it is contraindicated to perform any type of elective eye surgery. Today, pre-treatment of the eyelids with warm compresses and a pH-controlled shampoo has become a routine exercise for the thousands of people undergoing ocular surgery in the U.S. on a daily basis.